Advances in preventing and controlling cancer and other chronic diseases are currently limited by the failure to translate and disseminate evidence-based knowledge/interventions (EBI's) into practice. The purpose of this proposal is to conduct research to study the dissemination and implementation of MOVE! (Managing Overweight/Obesity for Veterans Everywhere). MOVE! is a national weight management program for veterans that is moving from pilot to full dissemination this year. Overweight and obesity are rapidly rising in the United States and interventions to combat this epidemic are desperately needed. Within the VA population, approximately 70% of veterans are overweight and or obese. The proposed research study will be conducted in partnership with a federal agency, the Veterans Affairs National Center for Health Promotion and Disease Prevention (VANCP), which is overseeing the dissemination of the program to a broad population through its national network of VA medical settings and community-based outpatient clinics. The US Veteran's Health Administration (VA) is the nation's largest health care organization, with 157 medical centers and 862 community-based out-patient clinics, 7.4 million enrolled patients, over five million active users of services, and 50 million out-patient visits/year. Thus, there is tremendous potential for high impact of programs disseminated and implemented effectively through the VA system, as well as potential to inform dissemination in other health systems. Our research team already has been collaborating with the VANCP and two VA clinical sites on a pilot dissemination project funded by NCI to incorporate and test EBI's that have the potential to strengthen the existing MOVE! program. We propose to study whether an innovative participant self-management intervention delivered primarily by veteran volunteers can address existing barriers to implementation of the current professionally-delivered and clinic-based MOVE! program. This new model will be called MOVE*VETS! (Volunteer Education and Tailored Self-management and support) and will include individualized computer-tailored printed health newsletters and motivational interviewing telephone calls delivered by volunteer veteran peer counselors. We will assess the impact of this alternative intervention delivery model on the overall dissemination and implementation of MOVE! using theory-based evaluation measures at both the participant level (participation and weight loss) and organizational levels of change.